Shrubs climbing. Stems terete, striate, densely villous. Petiole 1-1.5 cm, sparsely villous; leaf blade lanceolate-oblong to narrowly oblong, 12-20 × 2-5 cm, leathery or papery, abaxially sparsely villous, glaucous, adaxially glabrous, veins pinnate, 8-12 pairs, base narrowly auriculate, sinus 2-5 cm deep, apex acute. Flowers in axils of leafy shoots or on old woody stems, solitary. Peduncle pendulous, 7-12 cm, villous; bractlets not seen. Calyx yellow with purple veins and blotches, 10-15 cm; tube geniculately curved, abaxially villous; basal portion of tube 50-60 × 15-20 mm; limb discoid, 8-13 cm in diam., shallowly 3-lobed or emarginate; lobes broadly rounded, slightly unequal. Anthers oblong, 4.5-5 mm. Gynostemium 3-lobed. Capsule not seen. Fl. Apr-Mar.